N-bromobutanimide → ETHYL 2-PHENYLTHIAZOLE-5-CARBOXYLATE

HRID 1397372Notes

Reaction equation

HRID 1397372 reaction equation
BrN1[C:6](=[O:7])[CH2:5][CH2:4]C1=O.[C:9]([NH2:17])(=[S:16])[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1.O1CCO[CH2:20][CH2:19]1.[OH2:24]>>[C:10]1([C:9]2[S:16][C:5]([C:6]([O:7][CH2:19][CH3:20])=[O:24])=[CH:4][N:17]=2)[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1

Participants

4

Reactant 3

HCID 67184N-bromobutanimideHCID 683563ThiobenzamideHCID 218864351,4-Dioxane--water (1/1)

Product 1

HCID 9899456ETHYL 2-PHENYLTHIAZOLE-5-CARBOXYLATEYield 17%

Conditions

Temperature
-10 °C

Procedure

Ethyl-3-ethoxyacryalate (4.0 g, 27.7 mmol) was dissolved in dioxane-H2O (30 ml, 1:1 v/v) and cooled to −10° C. N-Bromosuccinimide (5.43 g, 30.5 mmol) was added to this solution and the reaction mixture was allowed to warm up to room temperature and further stirred for 1 h. Thiobenzamide (3.8 g, 27.7 mmol) was then added and the reaction mixture was further heated to 80° C. for 1 h. The reaction mixture was then cooled to room temperature and quenched with aqueous ammonia solution. The organic product was extracted with EtOAc and combined extracts were washed with H2O and brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel 60-120 mesh, eluent 5-10% EtOAc in petroleum ether) to afford ethyl 2-phenylthiazole-5-carboxylate (1.1 g, yield 17%) as a yellow solid. 1H NMR (300 MHz, CDCl3) δ 8.43 (s, 1H), 8.01-7.98 (m, 2H), 7.48-7.48 (m, 3H), 4.44-4.37 (q, J=7.2 Hz, 2H), 1.44-1.39 (t, J=7.2 Hz, 3H). MS (ESI) m/z: Calculated for C12H11NO2S: 233.05. found: 234.0 (M+H)+.

Workup

  1. temperatureto warm up to room temperature
  2. temperaturethe reaction mixture was further heated to 80° C. for 1 h
  3. temperatureThe reaction mixture was then cooled to room temperature
  4. customquenched with aqueous ammonia solution
  5. extractionThe organic product was extracted with EtOAc
  6. washwere washed with H2O and brine
  7. dry with materialdried over anhydrous sodium sulfate
  8. concentrationconcentrated under reduced pressure
  9. customThe crude product was purified by column chromatography (silica gel 60-120 mesh, eluent 5-10% EtOAc in petroleum ether)

Sources & evidence

ORD record
ord-7cb2c1e2582043cb879deec634a0745d
Source dataset
uspto-grants-2014_12
Patent number
US08901156B2

Reaction notes

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